Lamp base



FIG. 1 is a top plan view of a lamp base showing my new design.

FIG. 2 is a side elevational view thereof.

FIG. 3 is a side elevational view taken at a 90° angle to FIG. 2.

FIG. 4 is a side elevational view taken at a 90° angle to FIG. 4.

FIG. 5 is a side elevational view taken at a 90° angle to FIG. 4.

FIG. 6 is a bottom plan view. 

The ornamental design for a lamp base, as shown. 